Optical scanners are widely used for optically probing extended objects or target scenes. In a typical scanner a light source sends out a beam of light; the beam is scanned across the object by, for instance, a scanning mirror; then the light returned from the object is collected by collection optics and is directed to a sensor. The sensor emits a signal to a controller for further analysis.
High-performance optical scanners typically use both high-power light beams and high-speed scanners in order to sample and sense distant target scenes with high temporal and spatial resolution with a good signal-to-noise ratio.